Surface appearance of poly lactic acid due to variations in material extrusion processing parameters

Area of Science:

• Additive Manufacturing
• Materials Science
• Polymer Engineering

Background:

• Material Extrusion (MEX) is a widely used 3D printing process.
• Optimizing MEX process parameters is crucial for achieving desired component quality.
• Polylactic Acid (PLA) is a popular biodegradable polymer for 3D printing applications.

Purpose of the Study:

• To investigate the impact of MEX process parameters on the surface quality of PLA components.
• To establish correlations between process variations, surface characteristics (roughness, grayscale), and mechanical properties.
• To evaluate the effectiveness of image analysis as a method for assessing surface quality.

Main Methods:

• Utilized Material Extrusion (MEX) to fabricate PLA components with varied process parameters (flow rate, nozzle temperature, fan speed).
• Employed straightforward image analysis to quantify surface grayscale variations.
• Measured surface roughness and conducted uniaxial tensile tests to determine mechanical properties (Young's modulus, tensile strength, strain at break).

Main Results:

• Significant correlations were found between process parameters and surface roughness/grayscale variations (50-60%).
• Grayscale image analysis results showed a strong match with surface roughness measurements.
• Flow rate and fan speed were identified as critical parameters influencing raster density, adhesion, and mechanical properties.

Conclusions:

• MEX process parameters substantially influence PLA surface quality and mechanical performance.
• Image analysis provides a viable and accurate method for assessing surface quality in MEX-processed PLA parts.
• Optimizing parameters like flow rate and fan speed is essential for controlling PLA component characteristics.